This application claims priority to Korean Application Number 10-2005-0018256 filed in Korea on Mar. 4, 2005, the entire contents of which is incorporated by reference in it entirety.
1. Field of the Invention
The present invention relates to a mobile communication terminal, and more particularly to a mobile communication terminal and method for compensating an automatic exposure of a camera to thereby shorten a time for the automatic exposure compensation and to improve the stability of the exposure compensation.
2. Description of the Related Art
Mobile communication terminals include various functions such as a camera function, a multimedia playing function, etc. in addition to the simple radio communication function. The camera and multimedia playing functions are gradually becoming more popular especially because the terminal is equipped with a digital camera with a high resolution and a color LCD (Liquid Crystal Display) screen.
Further, graphic data such as icons indicating various information (e.g., reception characteristics, a battery capacity, messages, bell/vibration, etc.) and menus are generally displayed on the color LCD. Pictures taken with the camera as well as streaming image data decoded by an MPEG-4 (Motion Picture Experts Group 4) Codec (Coder and Decoder) may also be displayed on the color LCD.
In addition, the mobile terminal digital camera uses a CCD (Charge Coupled Device), a CMOS (Complementary Metal Oxide Semiconductor), etc. as a photographing device, and also includes an AE (Automatic Exposure) function for automatically adjusting an amount of light with respect to images photographed by the digital camera.
A related art mobile terminal method for compensating an automatic exposure of a camera adjusts an aperture opening time of a lens, when an average luminance value of a photographed image goes beyond a range of a particular threshold value. Accordingly, the amount of light for an image to be photographed is controlled so as to display an optimum image. That is, in the related art compensating method, the amount of light for the image being photographed is increased by lengthening the aperture opening time, while the amount of light is decreased by shortening the aperture opening time.
However, in the related compensating method, the time required for compensating the automatic exposure to achieve a particular target luminance value takes too long. Further, the stability for compensating the automatic exposure to achieve the particular target luminance value is degraded.